Cookbook Show UI Integration:
- Minor restructure to page to allow for full bleed columns
- Equal height columns on show page
- Format pre and code tags for command line examples
- Format cookbook heading and sidebar content
- Underscore category names in category nav
- Add template views for kaminari pagination
- Format pagination against Foundation conventions
- Restyle breadcrumbs
- Add previous page chevron next to cookbook name
- Separate cookbook show into partials for reuse for cookbook version
  show
Merge pull request #224 from opscode/show-cookbook-ui-integration

Cookbook Show UI Integration
Make cookbook url validation stricter.

source_url and issues_url are validated with a stricter regex that is less lax
than URI.regexp.
Create validate methods for source and issues urls
Use validate_url for Cookbook URL validations.